Underground conduit for electric conductors.



No. 680,|5|. VPatented Aug. 6, l90l. C. A. W. HULTMAN;

UNDERGFHIUND` CONDUIT FOR ELECTII/C,(IONDIHPTRSl (Application filed Mar.23, 1901.)

(no Model.) I awww-snee: l.

lllllllll/lll//zl/I/l//Il l l//l 4 Tu: ianms Frans cu. moTmLrmo.,wnsmuarm u c No. 680,|5I. Patented Aug. 6,l |90I. C. A. W. HULTMAN.

UNDERGROUND CONDUIT FUR ELECTRIC CONDUCTOBS.

(Application filed Mar. 23, 1901.) (No Model.)

2 S'heets-Shget 2.

UNITED STATES PATENT OFFICE.

CARL A. W. HULTMAN, OF STOCKHOLM, SWEDEN.

UNDERGROUND CONDUIT FOR ELECTRIC CONDUCTORS.

SPECIFICATION forming part Of Lettells Patent NO. 680,151, dated August6, 1901. Application tiled March 2.3, 1901. Serial No. 52,543. (Nomodel.)

To @ZZ whom, it may concern.:

Be it known that I, CARL AXEL WILHELM HKULTMAN, a subject of the King ofSweden and Norway, residing at Stockholm, in the Kingdom of Sweden, haveinvented certain new and useful Improvements in Underground Conduits forElectric Conductors; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and to figuresof reference marked thereon, which form a part of this specificalfion.

This invention relates to underground conduits, and has for its objectanovel construction of a sectional conduit for electric cable,telegraph-Wires, and the like and to provide a water and gas tightconduit the sections of which are capable of yielding at their joints toa limited extent in order to adapt themselves to the settling of theground in which they are placed.

Referring to the drawings, in which like parts are4 similarlydesignated, Figure l is a vertical longitudinal sectional View of oneform of conduit. Fig. 2 is a similar form showing a conductive sleeve;Fig. 3, a like view showing butt-joints; Fig. 4, a cross-section on line44 of Fig.1; Fig. 5,a cross-section showing ythe built-up inner conduit;Fig. 6, a vertical longitudinal section showing interfitting ends; Fig.7, a section on line 7 7 of' Fig. 6, and Fig. S a section on line 8 8 ofFig. 6.

The inner or cable-carrying tubes 10 are made in one piece, as shown inFigs. 1, 2, 3, and 4, of terra-cotta, cement, artificial wood, orsimilar materials, are made of suitable lengths, and incased in anenvelop or sheetmetal casing l1, one end of which preferably projectsbeyond the tubes or groups of tubes 10 and is made tapering from end toend or made larger or flaring, so that at the projecting portion theinner sections will have interfitting ends. These sections are thenplaced in terra-cotta conduits 12, molded or baked iu a suitable form,whose ends are variously formed, so as to be put together to form acontinuous conduit.

Between the inner sections of the sets of tubes 10 are placed suitablegaskets 13,which may be made of tarred rope, hemp, jute, or

other suitable gasket material capable of forming a yielding water-tightjoint. The terra-cotta conduits 12 at their abutting joints are providedwith similar gaskets or packings 13,, and the vacant space or pocket 14,formed between the suitably-shaped ends of these conduits 12 and theinner conduit, is then filled With cement or suitable filling material,thus making a yielding gas and Water tight joint. This filling materialmay be composed of goudron dissolved in a suitable solvent, such asmineral oil, paraffin-oil, or equivalent material. y

In Fig. 2 I have shown the exterior terracotta conduit 12 as providedwith stepped ends, around which is placed a ring of similar material 15,the joints between said ring and terra-cotta sections being packed by asuitable packing 139, laid in the angle between the anges 16a of thestepped ends.

In Fig. 3 I have shown the terra-cotta section provided with flanges 16,arranged to be alined to form an abutting joint provided with recesses17 for the packing material. These ilanges are formed flush with theexterior Wall of the conduit 12 instead of with the interior wall, asshown in Fig. 2, the space between the flanges and the interior Wallserving for the reception of the lute or flexible Water-tight packing.

In lieu of forming the interior or tubular portion of the conduit in onepiece of cement, terra-cotta, or similar material, as shown in sectionin Fig. 4, I may make this interior portion as built-up sections, asshown in Fig. 5. These conduit-sections are made of suitably formedblocks of Wood, artificial Wood, or the like arranged to be placedtogether so as to provide through passages or tubes 10. As shown, theseforms on the outer portion of the inner conduit-section aresector-shaped blocks 18, having cut-away portions at their 'corners thatform the tubespaces 10, while the inner blocks 19 are substantiallytriangular and also having cutaway corncrs for a like purpose. Thesesectional blocks may be surrounded With an envelop of sheet metal,tarred paper, sheet-celluloid, or similar waterproofing material, andthis material may extend beyond one end of the inner conduit-section andbe somewhat enlarged or iiared, so as to form a socket for the receptionof the end of the next adjoining roo result.

section in a manner similar to the forms shown4 tend beyond theconduit-section proper, leaving an equal pocket at its opposite end forthe reception of the projecting end or ends of the pipes of theadjoining section, such a construction being shown in Fig. 6.

The pipes 20 are placed in a conical water and gas proof envelop 11a andheldin place by cement or similar material 21, so as tomake a rigidinner conduit-section, one of the pipes here shown for an example as acentral one of a group of seven, all of which are of substantially thesame length, has one end, as

shown at 22, projecting beyond the remaining tubes, leaving the pocketat its opposite end for the reception of the projecting end of the tubeof the adjoining section. These tubes,with their envelops ll,form arigid conduit-section arranged to be interfitted at their ends, packedwith the packing-ring 13, and areinserted in a suitable tubularterra-cotta sectional conduit 12, also arranged to have interlittingends, between which the packingring 13a is placed and the pocket `filledwith a suitable lute 23. The method of filling this pocket with such alute may be such as eXigencies of construction would require; but inFig. 8 I have shown a method of filling this pocket. Holes are formed inthe flange of the overlapping terra-cotta section 12, one of which, 24,is for the reception of a funnel,l through which the lute 23 is poured,and when the vent-hole 25 appears full the joining of two adjacentsections will be complete.

It is of course obvious that I may omit the terra-cotta conduit-sections 12 and simply lay the inner conduit-sections,which containthe cable-carrying tubes 10 20, in a bed of cement. The sections sojoined will be flexible at their joints and readily give and conform tothe settlement of the ground in which they are laid, thus preventing thedeleterious and destroying iniiuence of water and gas that pass throughcracks in the conduit and corrode the cables or wires.

Having thus described my invention, what I claim as new therein, anddesire to secure by Letters Patent, is-

1. A conduit for electric conductors comprising sections arranged end toend and having one or more passages for a conductor or conductors and awaterproof sheathing for each of said sections constructed to telescopeonto the sheathingof an adjacent section, for the purpose set forth.l

2. A conduit for electric conductors comn prising sections arranged endto end and hav'- ing one or more passages for a conductor or conductors,one or more of said passages projecting from one end of a section andtelescoping into the corresponding passage or passages of an adjacentsection, and a waterproof sheathing for each of said sectionsconstructed to telescope onto an adjacent section, for the purpose setforth.

3. A conduit for electric conductors comprising sections arranged end toend and having one or more passages for a conductor or conductors, awaterproof sheathing for each of said sections of greater length thanthe latter and having its portion projecting from one end made outwardlyaring and telescopin gonto the sheathing of an adjacent section, for thepurpose set forth.

4. A conduit for electric conductors comprising sections arranged end toend and having one or more passages for a conductor or conductors, and asheathing for each of said sections constructed to telescope onto anadjacent section; in combination with an inclosing structure made ofsections of less length than the,conduitsections and arranged about thesame to leave a gap at the telescopic connection vbeween theconduit-sections, a waterproof luting filling said gaps and thetelescopic joints, and a bridge bridging the gap between the sections ofthe inclosing structure, for the purpose set forth.

5. A sectional conduit for electric conductors, comprisingconduit-sections and telescopically intertting sheaths inclosiug saidsections, for the purpose set forth.

6. A conduit for velectric conductors comprising sections arranged endto end and having one or more passages for a conductor or conductors,vand a sheathing for each of said sections constructed to telescope ontoan adjacent section; in combination with an inclosing structure made ofsections of less length than the conduit-sections and arranged about thesame to leave a gap at the tele-- scopic connection between theconduit-sections, a Waterproof more or less flexible or elastic lutingfilling said gaps and the telescopic joints, and a bridge bridging thegap between the sections of the inclosing structure, for the purpose setforth. 7 A conduit for electric conductors comprising sections arrangedend to end and having one or more passages for a conductor orconductors, and a waterproof sheathing of a more or less flexiblematerial for each of said sections constructed to telescope onto thesheathing of an adjacent section, for the purposes set forth.` f

In testimony that I claim the foregoing as my invention I have signed myname in presence of two subscribing witnesses.

CARL A. W. HULTMAN.

Witnesses:

PHILIP F. LARNER, HENRY ORTH, Jr.

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